import java.util.Scanner; 
public class Three {
    public static void main(String[] args) {
         Scanner in = new Scanner(System.in );
         int height, width;
         char status;
         height = in.nextInt();
         width = in.nextInt();
         Board board = new Board(height, width);
         status = board.getStatus();
         System.out.print(status);
    }
 }
class Board { 
     int height, width; 
     public Board(int height, int width) {
        this.height = height;
        this.width = width;
    } 
     public char getStatus() {
         if (height <= width) {
             return status(1);
        } 
         else {
            return status(1.0);
         }
     } 
     public char status(double rate) {
        System.out.println("B");
        return 0;
     }
 
     public char status(int rate) {    
        System.out.println("A");
        return 0;
    }
 }